Effects of daily mean temperature on sudden death among residents of Pudong New Area, Shanghai: A time-series study

Siyue HAN; Lianghong SUN; Hua CHEN; Xiaobin QU; Jiayi SHENG; Caixia HU; Sen WANG; Yichen CHEN; Caoyi XUE

Return

Effects of daily mean temperature on sudden death among residents of Pudong New Area, Shanghai: A time-series study

VernacularTitle:日均气温对上海市浦东新区居民猝死影响的时间序列研究
Author: Siyue HAN ¹ ; Lianghong SUN ¹ ; Hua CHEN ¹ ; Xiaobin QU ¹ ; Jiayi SHENG ¹ ; Caixia HU ¹ ; Sen WANG ¹ ; Yichen CHEN ¹ ; Caoyi XUE ¹
Author Information

1. Office of General Operations, Shanghai Pudong New Area Center for Disease Control and Prevention (Shanghai Pudong New Area Health Supervision Institute), Fudan University Pudong Institute of Preventive Medicine, Shanghai 200136, China.
Publication Type:Investigation
Keywords: sudden death; daily average temperature; distributed lag non-linear model; attributable disease burden; time-series analysis
From: Journal of Environmental and Occupational Medicine 2026;43(8):959-966
CountryChina
Language:Chinese
Abstract: Background The crude mortality rate of sudden death has shown a steady upward trend. Pudong New Area, Shanghai, is a highly urbanized and densely populated district that is substantially affected by the urban heat island effect and has experienced frequent extreme temperature events in recent years. However, evidence on the association between ambient temperatures and sudden death among local residents remains limited. Objective To examine the association between daily mean temperature and sudden death in Pudong New Area, and to provide evidence for reducing temperature-related risks of sudden death. Methods Data on sudden death, meteorological factors (daily average temperature, daily average relative humidity, and daily average air pressure), and air pollutants [inhalable particulate matter (PM₁₀), sulfur dioxide (SO₂), and nitrogen dioxide (NO₂)] in Pudong New Area from 2016 to 2021 were collected. A distributed lag non-linear model was used to examine the associations of daily mean temperature with total sudden death and sudden death due to cardiovascular and cerebrovascular diseases, including lagged and cumulative effects (lag0, 0-3, 0-7, 0-14, and 0-21 d). Stratified analyses were performed by sex, age, and education level to identify vulnerable populations. The temperature attributable burden of sudden death was assessed by calculating attributable number (AN) and attribute fraction (AF). Results A total of 19458 sudden deaths were reported in Pudong New Area from 2016 to 2021, of which 11082 (56.95%) were due to cardiovascular and cerebrovascular diseases. Both low (P₅, 4.6 ℃) and high (P₉₅, 30.2 ℃) temperatures were associated with increased risks of sudden death. The cumulative risks associated with low temperature peaked at lag 0-21 d for both total sudden death and sudden death due to cardiovascular and cerebrovascular diseases. In contrast, the cumulative risks associated with high temperature peaked at lag 0-7 d for total sudden death and at lag 0-3 d for sudden death due to cardiovascular and cerebrovascular diseases. Stratified analyses showed that females, individuals aged ≥65 years, and those with primary school education or below were more sensitive to low temperature; whereas females, individuals aged <65 years, and those with secondary school education or above were more sensitive to high temperature. Using 21.5 ℃ as the minimum mortality temperature, the AN of total sudden deaths attributable to non-optimal temperature was 3791 (95%CI: 1853, 5587), with an AF of 20.41% (95%CI: 9.47%, 28.94%); the AN attributable to low temperature was 3358 (95%CI: 1087, 5062), with an AF of 17.26% (95%CI: 5.89%, 26.01%), whereas the AN attributable to high temperature was 225 (95%CI: −274, 655), with an AF of 2.03% (95%CI: −2.53%, 5.78%). For sudden deaths due to cardiovascular and cerebrovascular diseases, the AN attributable to non-optimal temperature was 2721 (95%CI: 1747, 5575), with an AF of 24.55% (95%CI: 9.59%, 28.65%); the AN attributable to low temperature was 2496 (95%CI: 988, 3562), with an AF of 22.53% (95%CI: 8.97%, 32.41%), whereas the AN attributable to high temperature was 614 (95%CI: −15, 1176), with an AF of 3.15% (95%CI: −0.08%, 6.02%). Conclusions Both low (P₅, 4.6 ℃) and high (P₉₅, 30.2 ℃) temperatures are associated with increased risks of sudden death in Pudong New Area, Shanghai. High temperature shows a relative short-term effect, whereas low temperature shows a stronger cumulative effect. Females, people ≥65 years, and individuals with primary school educational attainment or below are more vulnerable to low temperature, while females, people <65 years, and those with secondary school educational attainment or above are more vulnerable to high temperature. The attributable burden of low temperature is greater than that of high temperature. Targeted health protection measures should be strengthened for vulnerable populations during extreme temperature events.